leds: add LM3533 LED driver

Add sub-driver for the LEDs on National Semiconductor / TI LM3533 lighting
power chips.

The chip provides 256 brightness levels, hardware accelerated blinking as
well as ambient-light-sensor and pwm input control.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Rob Landley <rob@landley.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Jonathan Cameron <jic23@cam.ac.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Documentation/ABI/testing/sysfs-class-led-driver-lm3533

+What:		/sys/class/leds/<led>/als_channel
+Date:		May 2012
+KernelVersion:	3.5
+Contact:	Johan Hovold <jhovold@gmail.com>
+Description:
+		Set the ALS output channel to use as input in
+		ALS-current-control mode (1, 2), where
+
+		1 - out_current1
+		2 - out_current2
+
+What:		/sys/class/leds/<led>/als_en
+Date:		May 2012
+KernelVersion:	3.5
+Contact:	Johan Hovold <jhovold@gmail.com>
+Description:
+		Enable ALS-current-control mode (0, 1).
+
+What:		/sys/class/leds/<led>/falltime
+What:		/sys/class/leds/<led>/risetime
+Date:		April 2012
+KernelVersion:	3.5
+Contact:	Johan Hovold <jhovold@gmail.com>
+Description:
+		Set the pattern generator fall and rise times (0..7), where
+
+		0 - 2048 us
+		1 - 262 ms
+		2 - 524 ms
+		3 - 1.049 s
+		4 - 2.097 s
+		5 - 4.194 s
+		6 - 8.389 s
+		7 - 16.78 s
+
+What:		/sys/class/leds/<led>/id
+Date:		April 2012
+KernelVersion:	3.5
+Contact:	Johan Hovold <jhovold@gmail.com>
+Description:
+		Get the id of this led (0..3).
+
+What:		/sys/class/leds/<led>/linear
+Date:		April 2012
+KernelVersion:	3.5
+Contact:	Johan Hovold <jhovold@gmail.com>
+Description:
+		Set the brightness-mapping mode (0, 1), where
+
+		0 - exponential mode
+		1 - linear mode
+
+What:		/sys/class/leds/<led>/pwm
+Date:		April 2012
+KernelVersion:	3.5
+Contact:	Johan Hovold <jhovold@gmail.com>
+Description:
+		Set the PWM-input control mask (5 bits), where
+
+		bit 5 - PWM-input enabled in Zone 4
+		bit 4 - PWM-input enabled in Zone 3
+		bit 3 - PWM-input enabled in Zone 2
+		bit 2 - PWM-input enabled in Zone 1
+		bit 1 - PWM-input enabled in Zone 0
+		bit 0 - PWM-input enabled

drivers/leds/Kconfig

@@ -50,6 +50,19 @@ config LEDS_LM3530
 	  controlled manually or using PWM input or using ambient
 	  light automatically.
 
+config LEDS_LM3533
+	tristate "LED support for LM3533"
+	depends on LEDS_CLASS
+	depends on MFD_LM3533
+	help
+	  This option enables support for the LEDs on National Semiconductor /
+	  TI LM3533 Lighting Power chips.
+
+	  The LEDs can be controlled directly, through PWM input, or by the
+	  ambient-light-sensor interface. The chip supports
+	  hardware-accelerated blinking with maximum on and off periods of 9.8
+	  and 77 seconds respectively.
+
 config LEDS_LOCOMO
 	tristate "LED Support for Locomo device"
 	depends on LEDS_CLASS

drivers/leds/Makefile

@@ -10,6 +10,7 @@ obj-$(CONFIG_LEDS_ATMEL_PWM)		+= leds-atmel-pwm.o
 obj-$(CONFIG_LEDS_BD2802)		+= leds-bd2802.o
 obj-$(CONFIG_LEDS_LOCOMO)		+= leds-locomo.o
 obj-$(CONFIG_LEDS_LM3530)		+= leds-lm3530.o
+obj-$(CONFIG_LEDS_LM3533)		+= leds-lm3533.o
 obj-$(CONFIG_LEDS_MIKROTIK_RB532)	+= leds-rb532.o
 obj-$(CONFIG_LEDS_S3C24XX)		+= leds-s3c24xx.o
 obj-$(CONFIG_LEDS_NET48XX)		+= leds-net48xx.o